The potential for an all-Williams championship match at the Italian Open was ended on Friday when both sisters crashed out of the draw.
Fifth-seeded Serena Williams never even took to the court for her quarter-final match due to back injury, handing a walkover victory to unseeded Frenchwoman Alize Cornet.
Williams suffered the injury on a practice court prior to the match with Cornet.
In quarter-final action on the other side of the draw, seventh-seeded Venus Williams was ousted 5-7 6-2 6-3 by defending champion and fourth seed Jelena Jankovic.
"(The back injury) just happened all of a sudden in practice," said Serena, who won the claycourt event in 2002.
"I just went for a shot and then my back got a little stuck, so that's basically how it happened. I didn't feel anything the last match, and I don't expect this to cause any problems with my preparation for the French (Open)."
The development keeps alive an impressive run by Cornet, who upset third seed and 2007 runner-up Svetlana Kuznetsova on Thursday.
The 18-year-old has been strong on clay this year with a 15-5 mark, including a runner-up effort in Acapulco.
Cornet will face number six Anna Chakvetadze in the round of four and Jankovic takes on second-seeded Maria Sharapova.
After a tough first two sets, Sharapova took control in the final set en route to a 6-7 (7/3) 7-5 6-2 victory over Patty Schnyder of Switzerland. Sharapova won the first three games of the final set.
Venus Williams was 17-3 at this event, which she won in 1999, and appeared primed for another run at the title after winning a bizarre first set that saw her and Jankovic combine for nine service breaks.
But Jankovic, who admitted on Thursday that she has been playing sick this week, settled down after that and broke Williams five times over the remaining two sets to claim her eight straight win here.
"I wasn't really holding any service games in the first set, and then that changed in the second," Jankovic said.
"I tried to go for it a little bit more, and I tried to play a little bit more aggressive, and it paid off."
The 23-year-old Serb would probably have preferred to avoid another meeting with Sharapova, who has taken four of five matches in their all-time series.
Additionally, Sharapova has been been one of top players on the WTA Tour this season with a 27-2 record and three titles.
The 21-year-old Russian will become the new world number one next week as a result of Justine Henin's sudden retirement on Wednesday.
Her Russian compatriot, Chakvetadze appears to be regaining her top 10 form after a dismal 4-7 stretch over her previous seven tournaments.
The world number eight advanced with a 6-2 3-6 6-1 victory over Bulgarian qualifier Tsvetana Pironkova, who posted the upset of the tournament when she knocked out top seed Ana Ivanovic in the second round.
WTA – Rome quarterfinal results:
6 – Anna Chakvetadze (Russia) def. Tsvetana Pironkova (Bulgaria) 6-2 3-6 6-1
4 – Jelena Jankovic (Serbia) def. Venus Williams (USA) 5-7 6-2 6-3
2 – Maria Sharapova (Russia) def. 9 – Patty Schnyder (Switzerland) 6-7 (7-3) 7-5 6-2
Alize Cornet (France) def. (5) Serena Williams (USA) w/o (back injury)
Fifth-seeded Serena Williams never even took to the court for her quarter-final match due to back injury, handing a walkover victory to unseeded Frenchwoman Alize Cornet.
Williams suffered the injury on a practice court prior to the match with Cornet.
In quarter-final action on the other side of the draw, seventh-seeded Venus Williams was ousted 5-7 6-2 6-3 by defending champion and fourth seed Jelena Jankovic.
"(The back injury) just happened all of a sudden in practice," said Serena, who won the claycourt event in 2002.
"I just went for a shot and then my back got a little stuck, so that's basically how it happened. I didn't feel anything the last match, and I don't expect this to cause any problems with my preparation for the French (Open)."
The development keeps alive an impressive run by Cornet, who upset third seed and 2007 runner-up Svetlana Kuznetsova on Thursday.
The 18-year-old has been strong on clay this year with a 15-5 mark, including a runner-up effort in Acapulco.
Cornet will face number six Anna Chakvetadze in the round of four and Jankovic takes on second-seeded Maria Sharapova.
After a tough first two sets, Sharapova took control in the final set en route to a 6-7 (7/3) 7-5 6-2 victory over Patty Schnyder of Switzerland. Sharapova won the first three games of the final set.
Venus Williams was 17-3 at this event, which she won in 1999, and appeared primed for another run at the title after winning a bizarre first set that saw her and Jankovic combine for nine service breaks.
But Jankovic, who admitted on Thursday that she has been playing sick this week, settled down after that and broke Williams five times over the remaining two sets to claim her eight straight win here.
"I wasn't really holding any service games in the first set, and then that changed in the second," Jankovic said.
"I tried to go for it a little bit more, and I tried to play a little bit more aggressive, and it paid off."
The 23-year-old Serb would probably have preferred to avoid another meeting with Sharapova, who has taken four of five matches in their all-time series.
Additionally, Sharapova has been been one of top players on the WTA Tour this season with a 27-2 record and three titles.
The 21-year-old Russian will become the new world number one next week as a result of Justine Henin's sudden retirement on Wednesday.
Her Russian compatriot, Chakvetadze appears to be regaining her top 10 form after a dismal 4-7 stretch over her previous seven tournaments.
The world number eight advanced with a 6-2 3-6 6-1 victory over Bulgarian qualifier Tsvetana Pironkova, who posted the upset of the tournament when she knocked out top seed Ana Ivanovic in the second round.
WTA – Rome quarterfinal results:
6 – Anna Chakvetadze (Russia) def. Tsvetana Pironkova (Bulgaria) 6-2 3-6 6-1
4 – Jelena Jankovic (Serbia) def. Venus Williams (USA) 5-7 6-2 6-3
2 – Maria Sharapova (Russia) def. 9 – Patty Schnyder (Switzerland) 6-7 (7-3) 7-5 6-2
Alize Cornet (France) def. (5) Serena Williams (USA) w/o (back injury)
